Note.—The early history of the turbine is one of considerable interest especially in view of the development of the steam, from the water turbine.
“M. Fourneyron, who began his experiments in 1823, erected his first turbine in 1827, at Pont sur l’Ognon, in France. The result far exceeded his expectations, but he had much prejudice to contend with, and it was not until 1834 that he constructed another, in Franche Comté at the iron-works of M. Caron, to blow a furnace. It was of 7 or 8 horse-power, and worked at times with a fall of only 9 inches. Its performance was so satisfactory that the same proprietor had afterwards another of 50 horse-power erected, to replace 2 water-wheels, which together, were equal to 30 horse-power. The fall of water was 4 feet 3 inches, and the useful effect, varied with the head and the immersion of the turbine, 65 to 80 per cent. Several others were now erected: 2 for falls of seven feet; 1 at Inval, near Gisors, for a fall of 6 feet 6 inches, the power being nearly 40-horse, on the river Epté, expending 35 cubic feet of water per second, the useful effect being 71 per cent. of the force employed.”
Fig. 120.
The Leffel-Samson turbine wheel is shown in the engraving, [Fig. 120, page 129], where N.N. represents the bottom casting of the case flanged to support the wheel by resting upon the bottom of the penstock.
The draft tube I is of conical shape as represented at J. J. to reduce the friction of discharge water which after performing its work in the wheel escapes at the bottom of the draft tube. This tube must always project into the tail water at least two or three inches. The gates H.H.H. are pivoted at the center so that they are balanced and are opened and closed with the least possible friction. These gates are operated by rods L. L., connecting with a rack and pinion which are manipulated by the operator as occasion requires, by an extension shaft from the coupling K, having a hand-wheel on top.
Fig. 121.